Back to EveryPatent.com
United States Patent |
5,293,441
|
Tanisawa
|
March 8, 1994
|
Optical device capable of reliably fixing a substrate to a package
Abstract
In an optical device comprising a substrate and a package for receiving the
substrate on a bottom surface of the package, a block is fixed to an upper
surface of the substrate by a low melting-point glass or a solder. The
block is made of a welding material and welded to a predetermined part on
a wall surface of the package. The substrate has at least one
photoelectric element or optical waveguide on the upper surface. An
optical fiber is fixed to the package and optically coupled to the
photoelectric element or the optical waveguide through a first perforation
of the package. The block may be welded to the wall surface of the package
made of a welding material. The substrate may have an internal surface
which defines a second perforation exposing a predetermined area of the
bottom surface. The block is brought into contact with the second internal
surface and the predetermined area and welded to the predetermined area.
Inventors:
|
Tanisawa; Yasuhisa (Tokyo, JP)
|
Assignee:
|
NEC Corporation (Tokyo, JP)
|
Appl. No.:
|
995705 |
Filed:
|
December 23, 1992 |
Foreign Application Priority Data
Current U.S. Class: |
385/92; 385/88 |
Intern'l Class: |
G02B 006/42 |
Field of Search: |
385/88-94
|
References Cited
U.S. Patent Documents
4474429 | Oct., 1984 | Yoldas et al. | 385/88.
|
4548466 | Oct., 1985 | Evans et al. | 385/90.
|
4615031 | Sep., 1986 | Eales et al. | 385/94.
|
4744626 | May., 1988 | Mery | 385/90.
|
5128956 | Jul., 1992 | Aoki et al. | 372/703.
|
5222170 | Jun., 1993 | Bargar et al. | 385/88.
|
Primary Examiner: Lee; John D.
Attorney, Agent or Firm: Foley & Lardner
Claims
What is claimed is:
1. An optical device comprising:
a substrate having an upper surface on which at least one photoelectric
element is formed;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with the substrate brought
into contact with said bottom surface, said package having a predetermined
part on said wall surface and an internal surface which defines a
perforation;
an optical fiber fixed to said package and optically coupled to said
photoelectric element through said perforation; and
a block fixed to said upper surface by a low melting-point glass, said
block being made of a welding material and welded to said predetermined
part.
2. An optical device as claimed in claim 1, wherein said upper surface has
a recessed surface which defines an indent for receiving said block, said
block being fixed to said recessed surface by said low melting-point
glass.
3. An optical device comprising:
a substrate having an upper surface on which at least one photoelectric
element is formed;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with the substrate brought
into contact with said bottom surface, said package being made of a
welding material and having an internal surface which defines a
perforation;
an optical fiber fixed to said package and optically coupled to said
photoelectric element through said perforation; and
a block fixed to said upper surface by a low melting-point glass, said
block being made of a welding material and welded to said wall surface.
4. An optical device as claimed in claim 3, wherein said upper surface has
a recessed surface which defines an indent for receiving said block, said
block being fixed to said recessed surface by said low melting-point
glass.
5. An optical device, comprising:
a substrate having an upper surface on which at least one photoelectric
element is formed;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with said substrate
brought into contact with said bottom surface, said package having a
predetermined part on said wall surface and an internal surface which
defines a perforation;
an optical fiber fixed to said package and optically coupled to said
photoelectric element through said perforation; and
a block soldered to said upper surface, said block being made of a welding
material and welded to said predetermined part for securing said substrate
to said package.
6. An optical device, comprising:
a substrate having an upper surface on which at least one photoelectric
element is formed;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with said substrate
brought into contact with said bottom surface, said package having a
predetermined part on said wall surface and an internal surface which
defines a perforation;
an optical fiber fixed to said package and optically coupled to said
photoelectric element through said perforation; and
a block soldered to said upper surface, said block being made of a welding
material and welded to said predetermined part, said upper surface having
a recessed surface which defines an indent for receiving said block, said
block being soldered to said recessed surface.
7. An optical device, comprising:
a substrate having an upper surface on which at least one photoelectric
element is formed;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with said substrate
brought into contact with said bottom surface, said package being made of
welding material and having an internal surface which defines a
perforation;
an optical fiber fixed to said package and optically coupled to said
photoelectric element through said perforation and
a block soldered to said upper surface, said block being made of a welding
material and welded to said wall surface for securing said substrate to
said package.
8. An optical device, comprising:
a substrate having an upper surface on which at least one photoelectric
element is formed;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with said substrate
brought into contact with said bottom surface, said package being made of
a welding material and having an internal surface which defines a
perforation;
an optical fiber fixed to said package and optically coupled to said
photoelectric element through said perforation; and
a block soldered to said upper surface, said block being made of a welding
material and welded to said wall surface, said upper surface having a
recessed surface which defines an indent for receiving said block, said
block being soldered to said recessed surface.
9. An optical device comprising:
a substrate having an upper surface on which at least one optical waveguide
is formed;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with the substrate brought
into contact with said bottom surface, said package having a predetermined
part on said wall surface and an internal surface which defines a
perforation;
an optical fiber fixed to said package and optically coupled with said
optical waveguide through said perforation; and
a block fixed to said upper surface by a low melting-point glass, said
block made of a welding material and welded to said predetermined part.
10. An optical device as claimed in claim 9, wherein said upper surface has
a recessed surface which defines an indent for receiving said block, said
block being fixed to said recessed surface by said low melting-point
glass.
11. An optical device comprising:
a substrate having an upper surface on which at least one optical waveguide
is formed;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with the substrate brought
into contact with said bottom surface, said package being made of a
welding material and having an internal surface which defines a
perforation;
an optical fiber fixed to said package and optically coupled to said
optical waveguide through said perforation; and
a block fixed to said upper surface by a low melting-point glass, said
block being made of a welding material and welded to said wall surface.
12. An optical device as claimed in claim 11, wherein said upper surface
has a recessed surface which defines an indent for receiving said block,
said block being fixed to said recessed surface by a low melting-point
glass.
13. An optical device, comprising:
a substrate having an upper surface on which at least one optical waveguide
is formed
a package having bottom and wall surfaces which define an installation
space for receiving said substrate with said substrate brought into
contact with said bottom surface, said package having a predetermined part
on said wall surface and an internal surface which defines a perforation;
an optical fiber fixed to said package and optically coupled to said
optical waveguide through said perforation; and
a block soldered to said upper surface, said block being made of a welding
material and welded to said predetermined part for securing said substrate
to said package.
14. An optical device, comprising:
a substrate having an upper surface on which at least one optical waveguide
is formed;
a package having bottom and wall surfaces which define an installation
space for receiving said substrate with said substrate brought into
contact with said bottom surface, said package having a predetermined part
on said wall surface and an internal surface which defines a perforation;
an optical fiber fixed to said package and optically coupled to said
optical waveguide through said perforation; and
a block soldered to said upper surface, said block being made of a welding
material and welded to said predetermined part, said upper surface having
a recessed surface which defines an indent for receiving said block, said
block being soldered to said recessed surface.
15. An optical device, comprising:
a substrate having an upper surface on which at least one optical waveguide
is formed;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with the substrate brought
into contact with said bottom surface, said package being made of a
welding material and having an internal surface which defines a
perforation;
an optical fiber fixed to said package and optically coupled to said
optical waveguide through said perforation; and
a block soldered to said upper surface, said block being made of a welding
material and welded to said wall surface for securing said substrate to
said package.
16. An optical device, comprising:
a substrate having an upper surface on which at least one optical waveguide
is formed;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with the substrate brought
into contact with said bottom surface, said package being made of a
welding material and having an internal surface which defines a
perforation;
an optical fiber fixed to said package and optically coupled to said
optical waveguide through said perforation; and
a block soldered to said upper surface, said block being made of a welding
material and welded to said wall surface, said upper surface having a
recessed surface which defines an indent for receiving said block, said
block being soldered to said recessed surface.
17. An optical device comprising:
a substrate having an upper surface on which at least one photoelectric
element is formed, said substrate having a first internal surface which
defines a first perforation;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with the substrate brought
into contact with said bottom surface, said bottom surface having a
predetermined area exposed by said first perforation, said package being
made of a welding material and having a second internal surface which
defines a second perforation;
an optical fiber fixed to said package and optically coupled to said
photoelectric element through said second perforation; and
a block brought into contact with said predetermined area and said first
internal surface, said block being made of a welding material and welded
to said predetermined area.
18. An optical device comprising:
a substrate having an upper surface on which at least one optical waveguide
is formed, said substrate having a first internal surface which defines a
first perforation;
a package having a bottom surface and a wall surface which define an
installation space for receiving said substrate with the substrate brought
into contact with said bottom surface, said bottom surface having a
predetermined area exposed by said first perforation, said package being
made of a welding material and having a second internal surface which
defines a second perforation
an optical fiber fixed to said package and optically coupled with said
optical waveguide through said second perforation; and
a block brought into contact with said predetermined area and said first
internal surface, said block being made of a welding material and welded
to said predetermined area.
Description
BACKGROUND OF THE INVENTION
This invention relates to an optical device which comprises a substrate,
the package for receiving the substrate, and an optical fiber fixed to the
package.
A conventional optical device is disclosed by Yasuhisa Tanisawa et al in a
U.S. patent application Ser. No. 881,187 filed on May 11, 1992 and
assigned to the instant assignee. In the manner which will later be
described more in detail, the conventional optical device comprises a
substrate, a package, and an optical fiber. The package has a bottom
surface and a wall surface which define in cooperation an installation
space for receiving the substrate with the substrate brought into contact
with the bottom surface. The substrate is attached to the bottom surface
by a resin binder. The package has a first internal surface which defines
a first perforation.
A plurality of photoelectric elements are formed on the substrate. A
plurality of optical elements, such as a lens and an optical filter, are
mounted on the substrate. The optical fiber is coupled to the optical
elements and the photoelectric elements through the first perforation of
the package.
Inasmuch as a thermal expansion coefficient of the resin binder is large, a
position of the substrate displaces in response to a change of
temperature. As a result, positions of the photoelectric elements and the
optical elements change in response to the change of temperature.
Inasmuch as a time of cure of the resin binder is several tens of minutes
to several hours, it is impossible to quickly manufacture the conventional
optical device.
Inasmuch as a gas is produced from the resin binder, the gas tarnishes the
photoelectric elements and the optical elements.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide an optical device
capable of reliably fixing a substrate to a package.
It is another object of this invention to provide an optical device which
can be quickly manufactured.
It is still another object of this invention to provide an optical device
in which a gas is not produced.
Other objects of this invention will become clear as the description
proceeds.
According to an aspect of this invention, there is provided an optical
device which comprises (A) a substrate having an upper surface on which at
least one photoelectric element is formed; (B) a package having a bottom
surface and a wall surface which define an installation space for
receiving the substrate with the substrate brought into contact with the
bottom surface, the package having a predetermined part on the wall
surface and an internal surface which defines a perforation; (C) an
optical fiber fixed to the package and optically coupled to the
photoelectric element through the perforation; and (D) a block fixed to
the upper surface by a low melting-point glass, the block being made of a
welding material and welded to the predetermined part.
According to another aspect of this invention, there is provided an optical
device which comprises (A) a substrate having an upper surface on which at
least one photoelectric element is formed; (B) a package having a bottom
surface and a wall surface which define an installation space for
receiving the substrate with the substrate brought into contact with the
bottom surface, the package being made of a welding material and having an
internal surface which defines a perforation; (C) an optical fiber fixed
to the package and optically coupled to the photoelectric element through
the perforation; and (D) a block fixed to the upper surface by a low
melting-point glass, the block being made of a welding material and welded
to the wall surface.
According to still another aspect of this invention, there is provided an
optical device which comprises (A) a substrate having an upper surface on
which at least one photoelectric element is formed; (B) a package having a
bottom surface and a wall surface which define an installation space for
receiving the substrate with the substrate brought into contact with the
bottom surface, the package having a predetermined part on the wall
surface and an internal surface which defines a perforation; (C) an
optical fiber fixed to the package and optically coupled to the
photoelectric element through the perforation; and (D) a block soldered to
the upper surface, the block being made of a welding material and welded
to the predetermined part.
According to yet another aspect of this invention, there is provided an
optical device which comprises (A) a substrate having an upper surface on
which at least one photoelectric element is formed; (B) a package having a
bottom surface and a wall surface which define an installation space for
receiving said substrate with the substrate brought into contact with the
bottom surface, the package being made of a welding material and having an
internal surface which defines a perforation; (C) an optical fiber fixed
to the package and optically coupled to the photoelectric element through
the perforation; and (D) a block soldered to the upper surface, the block
being made of a welding material and welded to the wall surface.
According to a different aspect of this invention, there is provided an
optical device which comprises (A) a substrate having an upper surface on
which at least one optical waveguide is formed; (B) a package having a
bottom surface and a wall surface which define an installation space for
receiving the substrate with the substrate brought into contact with the
bottom surface, the package having a predetermined part on the wall
surface and an internal surface which defines a perforation; (C) an
optical fiber fixed to the package and optically coupled with the optical
waveguide through the perforation; and (D) a block fixed to the upper
surface by a low melting-point glass, the block made of a welding material
and welded to the predetermined part.
According to another different aspect of this invention, there is an
optical device which comprises (A) a substrate having an upper surface on
which at least one optical waveguide is formed; (B) a package having a
bottom surface and a wall surface which define an installation space for
receiving the substrate with the substrate brought into contact with the
bottom surface, the package being made of a welding material and having an
internal surface which defines a perforation; (C) an optical fiber fixed
to the package and optically coupled to the optical waveguide through the
perforation; and (D) a block fixed to the upper surface by a low
melting-point glass, the block being made of a welding material and welded
to the wall surface.
According to still another different aspect of this invention, there is
provided an optical device which comprises (A) a substrate having an upper
surface on which at least one optical waveguide is formed; (B) a package
having bottom and wall surfaces which define an installation space for
receiving the substrate with the substrate brought into contact with the
bottom surface, the package having a predetermined part on the wall
surface and an internal surface which defines a perforation; (C) an
optical fiber fixed to the package and optically coupled to the optical
waveguide through the perforation; and (D) a block soldered to the upper
surface, the block being made of a welding material and welded to the
predetermined part.
According to yet another different aspect of this invention, there is
provided an optical device which comprises (A) a substrate having an upper
surface on which at least one optical waveguide is formed; (B) a package
having a bottom surface and a wall surface which define an installation
space for receiving the substrate with the substrate brought into contact
with the bottom surface, the package being made of a welding material and
having an internal surface which defines a perforation; (C) an optical
fiber fixed to the package and optically coupled to the optical waveguide
through the perforation; and (D) a block soldered to the upper surface,
the block being made of a welding material and welded to the wall surface.
According to a further different aspect of this invention, there is
provided an optical device which comprises (A) a substrate having an upper
surface on which at least one photoelectric element is formed, the
substrate having a first internal surface which defines a first
perforation; (B) a package having a bottom surface and a wall surface
which define an installation space for receiving the substrate with the
substrate brought into contact with the bottom surface, the bottom surface
having a predetermined area exposed by the first perforation, the package
being made of a welding material and having a second internal surface
which defines a second perforation; (C) an optical fiber fixed to the
package and optically coupled to the photoelectric element through the
second perforation; and (D) a block brought into contact with the
predetermined area and the first internal surface, the block being made of
a welding material and welded to said predetermined area.
According to a yet further different aspect of this invention, there is
provided an optical device which comprises (A) a substrate having an upper
surface on which at least one optical waveguide is formed, the substrate
having a first internal surface which defines a first perforation; (B) a
package having a bottom surface and a wall surface which define an
installation space for receiving the substrate with the substrate brought
into contact with the bottom surface, the bottom surface having a
predetermined area exposed by the first perforation, the package being
made of a welding material and having a second internal surface which
defines a second perforation; (C) an optical fiber fixed to the package
and optically coupled with the optical waveguide through the second
perforation; and (D) a block brought into contact with the predetermined
area and the first internal surface, the block being made of a welding
material and welded to the predetermined area.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic sectional view of a conventional optical device;
FIG. 2 is a schematic perspective view of an optical device according to a
first embodiment of this invention;
FIG. 3 is a schematic perspective view of an optical device according to a
second embodiment of this invention; and
FIG. 4 is a schematic sectional view of an optical device according to a
third embodiment of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, a conventional optical device will first be described
for a better understanding of this invention. The conventional optical
device comprises an insulator substrate 11 and a package 13. The substrate
11 is made of silicon. The package 13 is made of a welding material and
has a bottom surface 15 and a wall surface 17 which in cooperation define
an installation space 19 for receiving the substrate 11 with the substrate
11 brought into contact with the bottom surface 15. The substrate 11 is
attached to the bottom surface 15 by a resin binder 21.
The substrate 11 has an upper surface 23. A first metal film (not shown) is
formed on the upper surface 23. A laser diode 25 is soldered onto the
first metal film. A first spherical lens 27 and a prism 29 are mounted on
the upper surface 23. The package 13 has a first internal surface 31 which
defines a first perforation. A first Kovar block 33 is located in the
first perforation. The first Kovar block 33 is welded to the first
internal surface 31 by a laser beam of a YAG laser (not shown).
An optical fiber 35 has an end welded to a first outside surface of the
first Kovar block 33 by the laser beam of the YAG laser. A first pipe
holder 37 is fixed to the first outside surface of the first Kovar block
33 and holds the first optical fiber 35. The first optical fiber 35 is
optically coupled to the laser diode 25, the first spherical lens 27, and
the prism 29 through the Kovar block 33.
Inasmuch as a thermal expansion coefficient of the resin binder 21 is
large, the position of the substrate 11 displaces in response to a change
of temperature. As a result, positions of the laser diode 25, the first
spherical lens 27, and the prism 29 change in response to the change of
temperature.
Inasmuch as a time of cure of the resin binder 21 is several tens of
minutes to several hours, it is impossible to quickly manufacture the
conventional optical device.
Inasmuch as a gas is produced from the resin binder 21, the gas tarnishes
the laser diode 25, the spherical lens 27, the prism 29, and the first
Kovar block 33.
Referring to FIG. 2, the description will proceed to an optical device
according to a first embodiment of this invention. Similar parts are
designated by like reference numerals.
A first photodiode 39 is soldered onto the first metal film formed on the
substrate 11. A second metal film (not shown) is formed on the upper
surface 23. A second photodiode 41 is soldered onto the second metal film.
A second spherical lens 43 and an optical filter 45 are mounted on the
upper surface 23.
The package 13 has a second internal surface 47 which defines a second
perforation. A second Kovar block 49 is located in the second perforation.
The second Kovar block 49 is welded to the second internal surface 47 by
the laser beam of the YAG laser.
A second optical fiber 51 has an end welded to a second outside surface of
the second Kovar block 49 by the laser beam of the YAG laser. A second
pipe holder 53 is fixed to the second outside surface of the second Kovar
block 49 and holds the second optical fiber 51. The first optical fiber 35
is optically coupled to the first photodiode 39, the laser diode 25, the
first spherical lens 27, the prism 29, and the optical filter 45. The
second optical fiber 51 is optically coupled to the second photodiode 41,
the second spherical lens 43, the prism 29, and the optical filter 45.
In the optical device being illustrated, the substrate 11 is not attached
to the bottom surface 15 by the resin binder 21. The upper surface 23 has
first through fourth recessed surfaces which define first through fourth
indents, respectively. First through fourth blocks 61, 62, 63, and 64 are
fixed to the first through the fourth recessed surfaces by first through
fourth low melting-point glass pieces. Each of the first through the
fourth blocks 61, 62, 63, and 64 is adjacent to the wall surface 17. Each
of the first through the fourth blocks 61, 62, 63, and 64 is made of a
welding material and is welded to the wall surface 17 by the laser beam of
the YAG laser.
The package 13 has a plurality of connectors 67. The laser diode 25 and the
first and the second photodiodes 39 and 41 are connected to connectors 67
by wire bonding. The package 13 has a wall edge 69. An upper cover 71 is
fixed on the wall edge 69.
Referring to FIG. 3, the description will proceed to an optical device
according to a second embodiment of this invention. Similar parts are
designated by like reference numerals.
An optical waveguide 73 is formed on the upper surface 23. The optical
waveguide 73 branches or fans out into three narrow or small waveguides
and has first through fourth ends. The first optical fiber 35, the laser
diode 25, and the first and the second photodiodes 39 and 41 are connected
to the first through the fourth ends of the optical waveguide 73.
In FIGS. 2 and 3, the package 13 may have first through fourth
predetermined parts on the wall surface 17. Each of the first through the
fourth predetermined parts is made of a welding material. The first
through the fourth blocks 61 to 64 are welded to the first through the
fourth predetermined parts. The first through the fourth blocks 61 to 64
may be soldered to the first through the fourth recessed surfaces.
Referring to FIG. 4, the description will proceed to an optical device
according to a third embodiment of this invention. Similar parts are
designated by like reference numerals.
The substrate 11 has a third internal surface 75 which defines a third
perforation. The bottom surface 15 has a predetermined area 77 exposed to
the installation space 19 through the third perforation. A fifth block 79
is brought into contact with the predetermined area 77 and the third
internal surface 75. The fifth block 79 is made of the welding material
and welded to the predetermined area 77 by the laser beam of the YAG
laser.
Top